// 实现这个项目的构建任务
const {src,dest,parallel,series,watch} = require('gulp')

const del = require('del')
const browserSync = require('browser-sync')

const loadPlugins = require('gulp-load-plugins')

const plugins = loadPlugins()
const bs = browserSync.create()

// const plugins.sass = require('gulp-sass')
// const plugins.babel = require('gulp-babel');
// const plugins.swig = require('gulp-swig')
// const plugins.imagemin = require('gulp-imagemin')

const clean = () => {
  return del(['dist','temp'])
}

const style = () => {
  return src('src/assets/styles/*.scss',{base:'src'})
    .pipe(plugins.sass({outputStyle:'expanded'}))
    .pipe(dest('temp'))
}

const script = () => {
  return src('src/assets/scripts/*.js',{base:'src'})
    .pipe(plugins.babel({presets:['@babel/preset-env']}))
    .pipe(dest('temp'))
}

const page = () => {
  return src('src/*.html',{base:'src'})
    .pipe(plugins.swig({cache:false}))
    .pipe(dest('temp'))
}

const image = () => {
  return src('src/assets/images/**',{base:'src'})
    .pipe(plugins.imagemin())
    .pipe(dest('dist'))
}

const font = () => {
  return src('src/assets/fonts/**',{base:'src'})
    .pipe(plugins.imagemin())
    .pipe(dest('dist'))
}
const extra = () => {
  return src('public/**',{base:'public'})
    .pipe(dest('dist'))
}

const serve = () => {
  watch('src/assets/styles/*.scss',style)
  watch('src/assets/scripts/*.js',script)
  watch('src/*.html',page)
  // watch('src/assets/images/**',image)
  // watch('src/assets/fonts/**',font)
  // watch('public/**',extra)
  watch([
    'src/assets/images/**',
    'src/assets/fonts/**',
    'src/*.html'
  ],bs.reload)
  bs.init({
    server:{
      notify:false,
      baseDir:['temp','src','public'],
      routes:{
        '/node_modules':'node_modules'
      }
    }
  })
}

const useref = () => {
  return src('temp/*.html',{base:'dist'})
    .pipe(plugins.useref({searchPath:['dist','.']}))
    .pipe(plugins.if(/\.js$/,plugins.uglify()))
    .pipe(plugins.if(/\.css$/,plugins.cleanCss()))
    .pipe(plugins.if(/\.html$/,plugins.htmlmin({
      collapseWhitespace:true,
      minifyCss:true,
      minifyJs:true
    })))
    .pipe(dest('dist'))
}
const compile = parallel(style,script,page)

//上线之前开发阶段
const build = series(clean,parallel(series(compile,useref),extra,image,font))
//上线打包构建
const develop = series(compile,serve)
module.exports = {
  clean,
  build,
  develop
}
